Incorporating the unshift method in JavaScript: A Step-by-

Question

Incorporating the unshift method in JavaScript: A Step-by-

I'm looking to create a new function with the following requirements:

Function add(arr,...newVal){

}

array = [1,2,3];
add(array,0)
console.log(array);        //I want this to output [0,1,2,3]

I tried creating the function similar to push like this:

Function add(arr,...newVal){
for(var i=0; i<arr.length; i++){
arr[arr.length]=newVal[i];
}return arr.length;
}

array = [1,2,3];
add(array,4)
console.log(array);        // Expected output is [1,2,3,4]

javascript arrays typescript function methods

Answer 1

Answer №1

function addToFront(arr, ...newValues) {
    let index = arr.length + newValues.length - 1;
    for(index; index >= newValues.length; index--) {
        arr[index] = arr[index - newValues.length];
    }

    for(index; index >= 0; index--) {
        arr[index] = newValues[index];
    }
    return arr;
}

Answer 2

function addToFront(arr, ...newValues) {
    let index = arr.length + newValues.length - 1;
    for(index; index >= newValues.length; index--) {
        arr[index] = arr[index - newValues.length];
    }

    for(index; index >= 0; index--) {
        arr[index] = newValues[index];
    }
    return arr;
}

Answer 3

Answer №2

Give this a shot:

const addFirst = (array, value) => {
    for(let index = array.length; index > 0; index--) {
        array[index] = array[index - 1];
    }
    array[0] = value;
    return array;
}

Answer 4

Give this a shot:

const addFirst = (array, value) => {
    for(let index = array.length; index > 0; index--) {
        array[index] = array[index - 1];
    }
    array[0] = value;
    return array;
}

Incorporating the unshift method in JavaScript: A Step-by-

Answer №1

Answer №2

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